High prevalence of autism in S Korea

10th May 2011

South Korea has a much higher prevalence of autism than the standard model for autism spectrum disorders (ASDs) would usually predict, according to a recent US study led by a Korean-American researcher.

The finding shows that doctors worldwide may be drastically underestimating the number of people with ASDs.

The researchers attempted to study meticulously a cross-section of the country's population, examining 55,000 children between the ages of 7 and 12 over a five-year period.

In total, one in 38 children had some form of ASD.

The number of people with ASD in South Korea was more than twice that usually reported in developed countries such as the US and in Europe.

In the US, studies on ASDs usually focus on children who are already enrolled in special education programmes.

And, in developing countries, such numbers are already biased by the fact that children whose parents do not opt for diagnoses are missed out.

Young-Shin Kim, of the Yale school of medicine's Child Study Centre, said that Goyang city, which hosted the study, had responded to the findings by providing comprehensive assessment and intervention services for all first-year primary school entrants.

She said she hoped that cities would follow Goyang's example, so that any population-based identification of children with ASD was accompanied by intervention services for those children and their families.

For the study, the researchers screened every child in the Ilsan district of the city of Goyang, finding that more than two-thirds of the ASD cases in the mainstream school population went untreated.

Kim said that, from the beginning, she and her research team had the feeling that they would find a higher autism prevalence than usual.

She said that the South Korean population was under-studied as a whole.

As a result of the finding, Autism Speaks, the autism advocacy organisation, plans to fund further research on children in India, South Africa, Mexico, and Taiwan.

Kim said that she and her research team concluded that worldwide autism prevalence may be considerably underestimated by researchers.

Study co-author Roy Richard Grinker, a cultural anthropologist at George Washington University in the US, said that Korean parent and teacher focus groups were used by the research team to identify local beliefs that might influence symptom reporting and to address stigma and misunderstandings related to ASD.

The study did not attempt to find idiosyncratic risk factors unique to the South Korean population.

However, Kim said that having a better understanding of the actual number of people affected by ASD would set the stage for genetic studies that may point to differences between populations.